Apparatus for drawing glass



@ uw? Mmmm! A. P.: WHITTEMORE. APPARATUS FOB DRAWING GLASS. A'PPLncAnoN minpzc. 1o. i920.

1,415,133, Patented May 9, .1922.

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APFARATUS FOR DRAWNG- GLASS.

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Specicaton of Letters Qatent.

Application filed December 16, 1920. Serial-No. 429,6?7. l

To all w from z5 may concern f Be it known that l, ALLAN l). VVHITTE- Monia, residing at Charleston, in the county of Kanawha and `@tate of lVest Virginia, a citizen of the United States, have invented or discovered certain new and useful. Im-- piovements in Apparatus for Drawing Glass, of which improvements the following is a specification.

ln the drawing of glass articles, and particularly window-glass cylinders, more or less difiiculty is caused by differences in thermal conditions at different points or portions of the bath of molten glass from which the varticle is drawn. This leads to the production' of what is known as thick and thin glass, that is, glass of ununiform thickness along a given cross-section, and sometimes to excessive breakage. Eorts have heretofore been made, with varying success, to remedy this condition, but the difficulty still persists. Y

lt is the object of the present invention to provide novel means which will be effective to overcome the difculty above stated, and insure the drawing of glass of uniform thickness.

ln the accompanying drawings I have shown an application ofthe invention in connection with the use of the wellfknown water-cooled ring in the drawing of a window-glass cylinder.

Figure l is a vertical section of the ring, and Figure 2 isa plan view, showing conventionally a cylinder being` drawn from a bath of molten glass lying beneath the ring.

It will be understood that the ring l is suspended immediately above the surface of theibath of molten glass, and is intended tov symmetrically enclose the point of draw and the lower portion of the rising cylinder. The ring has the usual internal channel 2, for the circulation of the cooling fluid, an inlet pipe 3 and an outlet pipe ll. Thus if the thermal conditions in the glass bath around the rising cylinder are uniform, the symmetrical cooling effect of the ring will insure a uniform thickness of cylinder wall on any given cross-sectional line.

In Figure 2 of the drawings, however, 'l have illustrated conventionally a cross-sectional view of the lower portion of the rising cylinder,I wherein, due to ununiformity in thermal conditions, its wall is shown at t as thicker than at other points in its circumference. to remedy' this condi-.tien

and to obtain uniformity of wall thickness provide removable' sectional shields or cooling-retarders 5, which are attached to the inner face of the ring l in the neighborhood of the point c, and which in shielding the cylinder from the cooling effect of the ring at that point will serve to locally conserve the heat of the Olass, and thus accomplish the thinning of that portion of the wall to normal.

The cooling retarder sections may be simply hung` on studs or hooks 6 arranged around the inner face of the ring l, or they may be otherwise removably secured thereto. They may be of any convenient size, and may be made of any material having heatinsulating qualities sufficient for the purpose, Metal pieces covered with asbestos ill generally be found suitable.

As is well understood, the thickness of a drawn glass article may be varied by varying the speed of draw. ln the example given, if the wall of the cylinder should draw abnormally thin at any point, the speed of draw may be lowered in order to bring that portion up to normal thickness, and at the same time the ring may be retarded at other portions, and the proper uniform thickness thus be attained. p

The invention has the advantage of practically perfect flexibility, since the pieces 5 may be hung at any desired point, .and removed again at any time` as strictly local conditions may require. Incipient observed tendencies to ununiformity may be immediately neutralized, and superior results in all cases be attained.

While l have described the invention as utilized in the drawing of glass cylinders, it will be obvious that it is applicable to the drawing of other shapes, such as a sheet, where a cooling body or bodies are used. It will also be recognized that it may be used in connection with any instrumentality, whether water-cooled or not, which may be employed for accelerating the cooling of the glass article being drawn, all such instrumentalities being herein comprehended by the general termucooler.

I claim as my invention:

l. In apparatus for drawing glass, a cooler arranged adjacent to the drawing point, and a removable shield arranged between said cooler and the article being drawn.

52, in appa-ratas fer drawing; a cooler .Patented lay, i922. y

the cooling effect of Y arranged adjacent to the drawing point, and

said cooler, and a shield detachably connected to one of said supports and adapted to locally retard the eect of said cooler upon the article being` drawn.

4. In apparatus for drawing glass cylinders, a cooling ring arranged to surround the cylinder adjacent to the drawing point, and a sectional shield detachably secured adjacent to the inner face of' Said ring :for 15 locally retarding its cooling etl'ect upon the article being drawn.

ln'testimony whereof I have hereunto set in y hand.

ALLAN P. WHrrTEMonn.

Witnesses MARK BEAZLEY, GEORGE M. ROBINSON. 

